Outdoor Weld Table vs Rust?

[mcman56]

I have some materials to build a weld table but it will most likely have to be outside. I have heard of outside tables but never seen one. What do you do about rust protection? This is in Sacramento so rain is just a winter thing.

[atomarc]

I would paint it with any typical 'Derusto' type paint from your local hardware store. It's SOP to hit the top of a welding table with a grinder held flat to the table before starting a project. This removes all the berries and shines up the surface to facilitate a good ground.

Welding outside complicates the MIG process if using a shielding gas...wind will blow the gas away and the weld will suffer. TIG will suffer as well. Bright sunlight makes it a bit more difficult to see the weld puddle through your welding hood too.

If you have no other option than outside, then you will just have to be aware of these variables and go for the gusto!

Stuart

[redneckalbertan]

A little bit of surface rust on the table won't hurt anything. A person should still be able to get a good ground. I work outside as a welder year round and don't have a problem with rust that a grinder does't fix. You can get cupped grinding disks to clean up the rabble top if a person wishes. They allow a person to keep the grinding disk flat when cleaning up the table without digging in with the grinding disk.

[warmstrong1955]

A little bit of surface rust on the table won't hurt anything.

Agreed.
I have a welding/cutting table outside. I just pushed 6" of snow off it a couple days ago. It has rust, places that are painted from over spray, no matter. I just don't have enough room in my shop for it, and when the weather reasonable, better to be outside anyway.

I had a similar table in SE Alaska. Still no big deal..... I just had to hit it here & there with a grinder more often when I needed to make some setups & jigs on it.

Bill

[steamin10]

A stainless restaurant table is a little light but solves the rust problem.

[Jim Jakosh]

Clean the steel very well and wipe with lacquer thinner and prime first.

The very best primer I have found for out door steel is Zinc Chromate primer. It is dark green and it actually sacrifices itself in a scratch to fill the area so it won't rust. I'm not sure where you can get since the GREEN people have been taking away all the good stuff that works! Try the Eastwood company.

For a weld table, though, the top will get burned and cut up on the top. If it gets rained on it is for sure going to rust unless you can find a piece of good high nickel stainless for the top surface- otherwise cover it with a piece of wood with plastic on top when not using it. The wood will help protect it from moisture if it does not get wet it self.

I used to get rust on my mill table and other tools in my barn here is Michigan from the temperature change. I just build a wood box to put over the vise and no more rust at all!!

[redneckalbertan]

If it gets rained on it is for sure going to rust unless you can find a piece of good high nickel stainless for the top surface-

If you are working with steel on a stainless table and are sliding pieces sound and bumping them on the table it, the table will begin to rust. Definitely take longer than a piece do mild steel plate but it will rust. Not to mention filings from grinding or leaving a piece of steel sitting on top for a few days.

A stainless top will stay clear of rust a long time if you do an exceptional job of keeping it clean. Bit it is not a cure all, and an expensive one at that!

[Harold_V]

A stainless top will stay clear of rust a long time if you do an exceptional job of keeping it clean. Bit it is not a cure all, and an expensive one at that!

Yep. Without being passivated after contact with ferrous material, you can expect stainless to rust superficially. The only real advantage is that is limited to just a surface rust---it doesn't penetrate as it would in mild steel. Passivation was a required treatment for all 300 series components where I was trained.

Harold

[steamin10]

Ok, I need help here. I worked on a fairly expensive stainless prop for my boat, and plished the whole thing with a fine abrasive disc. Now it looks stripey with all the shadow rust hanging out in swirls. So I suppose that is the iron taking color from the oxides, and bleeding over the stainless. Some wipes off, some is rather stubborn.

So how do I passivate the surface, not that it hurts the performance, just looks bad. is it just an acid dip to remove the available iron, or something more complex?

[Harold_V]

I don't recall the spec. by which we passivated stainless components where I was trained, but it was spelled out in the traveler. The passivation was outsourced to a third party (a finishing house), one which was certified to perform to government specs.

On one occasion, when I was self employed, I had to passivate a series of components for a pair of aerial surveillance film developing units, which I built for the air force. My memory has grown dim, but what little I recall is that it is accomplished with dilute nitric acid and potassium or sodium dichromate solution, heated to about 130° F, with parts soaked for a prescribed period of time. Fortunately, I was involved in gold refining at the time, so I had the required chemicals on hand, along with a fume hood. Today, the acquisition of nitric acid borders on the impossible for the common man.

I have been lead to believe that there are other methods of passivation, but I am not the least bit familiar with them.

What I can tell you is that passivation does not alter size. It removes free iron from the surface of stainless, and creates an oxide that protects the elements within the stainless alloy.

Stainless that has been worked with common cutting tools tends to rust on the surface, pretty much as you described. Even raw stock which has been abraded in handling and exposed to the elements often bears rusted scratches.

Harold

[ken572]

All,

All the Stainless welds I did at PDI in my past working life,
I would passivate in 100% nitric acid at room temperature for
15 minutes and then a good rince in 30 meg ohm D.I. water and
we were done for the life of the stainless. Memories

Ken.

[GlennW]

I would passivate in 100% nitric acid